六株乳杆菌胃肠道定植能力分析

Study on the colonization ability of six strains of Lactobacillus in gastrointestinal tract

目的分析确定Lactobacillus Acidophilus(L.acidophilus)1.1等六株乳杆菌胃肠道定植能力强弱。方法通过模拟人体胃酸环境(pH 3)和高胆盐环境(胆盐含量:0.1%～0.3%),及用胶原蛋白和人结肠癌细胞SW-480模拟人肠道黏附环境,利用MTT法分别测定六株乳杆菌在酸性和高胆盐环境下37℃作用4 h后的存活菌率及与黏附介质作用1 h后的黏附率。结果六株乳杆菌均具有一定的耐酸和耐胆盐能力,以及不同程度的胶原蛋白及肠道细胞黏附能力,其中以L.acidophilus 1.2相对最为突出。结论 L.acidophilus 1.2等六株乳杆菌均能够不同程度的黏附定植在胃肠道中,发挥其益生作用,是较为理想的胃肠道微生态制剂候选菌株。

Purpose To study the colonization ability of 6 strains of Lactobacillus in gastrointestinal tract. Methods Lactobacillus were cultured at 37℃ for 4 h in MRS broth with high concentration of acid （pH 3） or bile salt to simulate human gastric or intestinal bile salt condition, respectively, and then the MTT assay was performed to determine the viability of different strains. The collagen and human colon cancer cells SW-480 were used to imitate the human intestinal environment and MTT assay was also be carried out to detect the adhesive ability of Lactobacillus after co-cultured for 1 h. Results All the six strains of Lactobacillus have acid and bile sale resistant ability, as well as adhesive ability to collagen and human colon cancer cells. Of these strains,Lactobacillus acidophilus 1.2 exhibited the greatest ability to pass the gastrointestinal tract and colonize in the colon. Conclusion Six strains of Lactobacillus, especially the Lactobacillus acidophilus 1.2, could adhere and colonize in the gastrointestinal tract, and then facilitate to play their healthcare functions in vivo. They can therefore be used as ideal probiotics candidates of functional food additives or drugs.